<template>
  <div class="subject">
    <span>{{ num1 }}</span>
    <span>+</span>
    <span>{{ num2 }}</span>
    <span>=</span>
    <input type="number" v-model.number="myResult" />
    <button @click="submit">提交</button>
  </div>
</template>

<script>
export default {
  props: ['data-id'],
  data() {
    return {
      num1: parseInt(Math.random() * 10) + 1,
      num2: parseInt(Math.random() * 10) + 1,
      myResult: '',
      flag: false
    }
  },
  methods: {
    submit() {
      if (this.myResult === this.totalNum) {
        this.flag = true
      } else if (!this.myResult) {
        this.flag = ''
      } else {
        this.flag = false
      }

      this.$emit('result', this.dataId, this.flag)
    }
  },
  computed: {
    totalNum() {
      return this.num1 + this.num2
    }
  }
}
</script>

<style scoped>
.subject {
  margin: 5px;
  padding: 5px;
  font-size: 20px;
}
.subject span {
  display: inline-block;
  text-align: center;
  width: 20px;
}
.subject input {
  width: 50px;
  height: 20px;
}
</style>
